Grinding wheels



April 14, 1959 A. A. MILLER GRINDING WHEELS Filed Jan. 24, 195s 4sheets-sheet 1 Ffa/ H6. 2.

April 14, 195,9

Filed Jan. 24, 1958 A. A. MILLER GRINDING WHEELS F/ca. i,

4 Sheets-Sheet 2 INVENTOR. Aer/fw@ fi /V/LEL frag N15/ April 14, A1959A. @MILLER 2,881,572v

GRINDING WHEELS Filed Jan. 24, 1958 4 Sheets-Sheet 3 INVENTOR. l www? /uif@ v qUnited tates Patat v2,881,572 Patented Apr- 14, 1.95.9

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GRINDING WHEELS Arthur A. Miller, McHenry, Ill., assignor to Arthur A.Miller and Lou C. Casanov, Waukegan, lll.

Application January 24, 1958, Serial No. 710,904

8 Claims. (Cl. 51191) My invention relates to improvements in grindingWheels.

My invention relates more particularly to grinding wheels of the typewhich may include a band or ring of abrasive such as sandpaper or thelike mounted on the periphery or tread portion of the grinding wheel,the tread portion being comparatively hard rubber so constructed that acertain amount of resiliency is given to the sanding surface of theWheel, and due to the r.p.rn. of the grinding wheel, it will expandwithin limits as required by the work for which it is intended.

In the accompanying description, by way of example, I am describinggenerally three constructions of grinding wheels, all of which aredesigned according to the same general principles, but which areconstructed for use at different rates of speed or revolutions perminute.

The principal object of the present invention is to provide an improvedconstruction of grinding wheels, each one of which has a tread portioncapable of guided movement during expansion, said movement being limitedaccording to the construction of the wheel, and each of the wheels beingprovided with pin members adapted to move in elongated slots in sideplates of the assembly in which the tread portion of the wheel ismounted.

A further object of the invention is to provide a con struction ofgrinding wheels of the same general type, yet which are modified in theexact details of construction to meet requirements of operation atvarious degrees of speed as has been found by trial and experience indesigning and constructing the grinding wheels herein referred to.

A further object of the invention is to provide a grinding wheel of thetype described that is easily and simply constructed, is made of aminimum of parts, and is capable of an eicient and long life as agrinding Wheel without becoming broken or out of order.

For a more comprehensive understanding of the details of constructionand the manner in which the structure and assembly is provided,reference is had to the following description and accompanying drawings,upon which:

Fig. 1 is a side elevational view of a comparatively small type ofgrinding wheel, generally for use in grinding inside castings, underfenders., and various other types of grinding in which a comparativelysmall grinding unit is required;

Fig. 2 is a ,front View thereof;

Fig. 3 is a vertical sectional View therethrough taken on the line 3-3of Fig. l;

Fig. 4 is a side elevational view of the tread member;

Fig. 5 is a side elevational view of a modified form of construction ofgrinding wheel adapted generally for work at the comparatively slowspeed of 1725 r.p.m.;

Fig. 6 is a crossrsectional view therethrough taken generally on theline 6-6 of Fig. 5;

Fig. 7 is a side elevational Iview of the tread member;

Fig. 8 is a `side `elevational view of the hub to which it is attached;

construction designed for use at a speed of 3450 rpm.;

and

Fig. l0 is a cross-sectional view thereof taken on the line 10-10 ofFig. 9.

In the embodiment of the invention which I have chosen to illustrate anddescribe the same, in Figs. l to 4 I have shown a comparatively smalltype of grinding wheel in which the tread member 10 may have acylindrical peripheral edge 12 about which an abrasive band 13 ispositioned. The tread member y10, as shown, is cylindrical in shape andis provided with an axial bore 14 for the reception of a spacer 15. Thetreadmember 10 also has circular recesses 20 and 22 for the reception ofside plates 24 and 26 positioned against both ends of the spacer 15. Theside plates 24 and 26 hav axial openings 28 and 30 to receive the driveshaft 16, the grinding wheel being mounted on the drive shaft andfastened by a nut member 32.

The side plates 24 and 26 may both be provided with elongated slots 34positioned at a point adjacent their peripheral edge, and the slotsbeing directed at an angle back from a center line through the inneredge of the slot and the axis o f the plate.

The tread member l0 is provided with rods 36 which extend parallel withthe bore 14 for the reception of the drive shaft, the ends of the rodsbeing received in the elongated slots 34 in the plates 24 and ,26, theends of the rods being headed as shown at 36a and 36b to aS- sembletogether the side plates, the pins and the tread member.

With the construction shown, and at a comparatively high rate of speed,such as about 10,000 r.p.m., `the tread member is expanded outwardlyuntil the pins 36 reach a point where they are generally directlyaligned with the surface of the abrasive belt and the axis of the treadmember so that each pin is a rm backing or support for the tread memberand abrasive belt at this point. Further, at the high rate of speedmentioned, the entire body of the tread member may be made of a,comparatively hard rubber, or a short thick web 17 as -shown mayconnect hub portion 19 and rim portion 21.

In Figs. 5 and 6 I have shown a form of the invention wherein thegrinding wheel 40 may have la circular ymetal hub 42 having an axialbore 44 to receive the drive shaft 46 of the motor 48. The tread memberof the grinding wheel may be a right-angle member 50 having the at outersurface 52 upon which the abrasive belt 54 is positioned, the annularperipheral shoulders 56 and 5S, and the body portion 60. Side plates inthe form of metal discs 62 and 64 are seated in the shallow recesses 65formed by the annular shoulders 56 and 58, the same being fastenedtogether and -to the hub 42 by means of a peripheral row of rivets 68.

The side plates 62 and 64 may be provided with elongated openings 70 inthe plate 62, and 72 in the plate 64, all of the elongated openingsbeing disposed at an obtuse angle from a radial line through the axisofthe plates. The four elongated openings l70 are adapted to receive theextended ends of pin members 474 which have lan enlarged head 76 setinto a suitable opening in the side of the body portion 60 of the treadmember, the pin 74 extending through the other endv of the tread memberand engaging the opening 70. In a similar manner, the pin members 78extend from the opposite side of the tread member through the same,having a head 80 embedded in a suitable opening in the tread member 60and with the ends of the pins engaging in the slots 72 of the side plate64.

The grinding wheel which I have provided in' the embodiment hereindescribed thus may .consist of a-tread member made of comparatively hardrubber, the same being mounted only upon the pin members 74 and 78 whichare mounted in the elongated slots in the side plates. The consistencyof the rubber is such that with this type of mounting and in grindingwheels of approximately 7 inches diameter, the wheel will operate withhigh efcieney at a comparatively low speed. The grinding wheel has beenfound to expand satisfactorily and effectively support the abrasive bandat 1725 r.p.rn., or any speeds from approximately 1200 r.p.m. to 2250r.p.m.

In the embodiment of the invention shown in Figs. 9 and 10, I have showna grinding wheel 82 which may include acylindrically shaped hub member84, side plates 86 and 88 and a tread member 90. The hub member 84 isprovided with an axial bore 92 to receive the drive shaft 94 of a motor96, the side plates 86 and 88 having the axial openings 87 and 89therethrough for the same purpose.

The tread member 90 may comprise a peripheral ring member 100 having theouter surface 102 to receive an abrasive band 104, the ring member 100being connected by -a medial web 106 with a hub portion 108 of the treadmember that has a bore 110 to receive the metal hub 84. The hub of thetread member may be fastened by means of a plurality of pin members 112to the side plates 86 and 88, the portion 108 also having a peripheralridge 114 through which the pins pass and the side plates 86 and 88having outwardly turned circular anges 116 to receive the ridges 114.

I provide a peripheral row of pin members 120 extending through bothsides of the peripheral ring member 100 and engaging in elongated slots122 in the side plates 86 and 88. Here again the elongated openings aredirected at a peak angle from the direction of rotation, so that whenpressure is applied to the abrasive band as by grinding a casting orother work piece, there is no tendency to compress the expanded treadfor the reason that the pin member in effect is backed up against a sidewall of the elongated opening, the side wall forming a solid bracing forthe expanded tread member at a comparatively high rate of speed.

The web 16 which connects the hub of the tread member to the peripheralring member of the same is of :a thickness such that the elasticity ofthe same permits the expansion of the grinding wheel by reason ofcentrifugal force, the expansion generally being absorbed in the webprovided.

While I have illustrated and described several modiications of thegrinding wheel capable of operating eflicently at different rates ofspeed ranging from 1200 r.p.m. to a maximum of 10,000 r.p.m., dependingupon the size and the solidity of the rubber tread member, it isapparent that the general principles of engineering involved are similarthroughout the various constructions. The extremely high rate of speedof the smaller wheel of necessity requires a denser rubber body portionthan that in either of the modifications shown in Fig. 6 or Fig. 10, oneof which is designed for a comparatively low rate of speed, and theembodiment shown in Fig. 10 being designed for a speed in theneighborhood of 3500 rpm. Both of the latter designs are of a type whichare readily capable of use with the ordinary quarter-inch drill motorsand other types of motors found in the home and home work shops, andthus present a grinding wheel for home use for a variety of purposes.

While I have illustrated and described a specific embodiment of theinvention and various modifications thereof, it will be apparent tothose skilled in the art that changes and modications may be made in theexact details shown and I do not wish to be limited in any particular;rather what I desire to secure and protect by Letters Patent of theUnited States is:

1. An abrasive wheel of the class described comprising a cylindrical hubadapted to be mounted on a motor shaft, a pair of circular side platesattached to the sides of said hub, each of said side plates havingelongated slots therein adjacent their outer periphery, a .rubber treadmember in the form of a ring having shallow bores on the sides of thesame to receive said side plates and pin members extending beyond theside Walls of said ring member and received in said elongated slots forcontrolling the position of said tread member, said slots directed backat an angle from the `direction of rotation and said side plates beingin planar alignment with the outer edges of said tread member.

2. An abrasive wheel of the class described comprising a cylindrical hubadapted to be mounted on a motor shaft, a pair of circular side platesattached to the sides of said hub, each of said side plates having aperipheral row of spaced elongated slots therein adjacent their outerperipheries, a rubber tread member in the form of a ring positionedbetween said side plates, a peripheral row of pin members thereinextending beyond each of the side walls of said ring member and receivedin the elongated slots of said side plates for controlling the positionof said tread member.

3. A circular abrasive wheel of the class described comprising acircular hub adapted to be mounted on a motor shaft, a pair of circularside plates attached to said hub, each of said side plates having anoutwardly turned circular flange and a row of elongated slots near theperipheral edge of the same, a rubber tread member comprising a hubportion adapted to 'it over said first mentioned hub, the hub portion ofsaid tread member having a circular ridge on each side of the samereceived in the circular flange of said side plates, said tread memberhaving a medial web extending outwardly from said hub and a peripheralring portion on the outer edge of said web, said peripheral ring portionhaving pins extending therethrough for engagement in the elongated slotsof said side plates.

4. A circular abrasive wheel of the class described comprising acircular hub adapted to be mounted on a motor shaft, a pair of circularside plates attached to said hub, each of said side plates having a rowof elongated slots near the peripheral edge of the same, a rubber treadmember comprising a hub portion adapted to it over said first mentionedhub, means fastening the hub portion of said tread member between saidside plates, said tread member having a medial web extending outwardlyfrom said hub and a peripheral ring portion on the outer edge of saidweb, said peripheral ring portion having pins extending therethrough forengagement in the elongated slots of said side plates.

5. A circular abrasive wheel of the class described comprising acircular hub adapted to be mounted on a motor shaft, a pair of circularside plates attached to said hub, each of said side plates having a rowof elongated slots near the peripheral edge of the same, a rubber treadmember comprising a hub portion adapted to t over said first mentionedhub, means fastening the hub portion of said tread member between saidside plates, said tread member having a medial web extending outwardlyfrom said hub and a peripheral ring portion on the outer edge of saidweb, said peripheral ring portion having pins extending therethrough forengagement in the elongated slots of said side plates, said slotsdirected back at an angle from the direction of rotation.

6. An abrasive wheel of the class described comprising a solidcylindrically shaped rubber tread member having a peripheral edge forreception of an abrasive band, a plurality of pins spaced about saidtread member near its peripheral edge and extending beyond both sideedges of said tread member, a drive shaft, a spacer on said shaft, amedial bore through said tread member for reception of said spacer anddisc-like side plates on each side of said tread member mounted on saiddrive shaft and fastened thereon against the ends of said spacer, and aplurality of elongated openings in said side plates near theirperipheral edges for receiving the ends of said pins for driving saidwheel, said tread member having shallow side bores therein and said sideplates positioned in said side bores whereby the side edges of saidtread member and the sides of said side plates are in planar alignment.

7. An abrasive wheel of the class described comprising a solidcylindrically shaped rubber tread member having a peripheral edge forreception of an abrasive band, a plurality of pins spaced about saidtread member near its peripheral edge and extending beyond both sideedges of said tread member, a drive shaft, a spacer on said shaft, amedial bore through said tread member for reception of said spacer anddisc-like side plates on each side of said tread member mounted on saiddrive shaft and fastened thereon against the ends of said spacer, and aplurality of elongated openings in said side plates near theirperipheral edges for receiving the ends of said pins for driving saidWheel, said elongated openings eX- tending outwardly from the axis ofsaid wheel at an angle back from the direction of rotation, said treadmember having shallow side bores therein and said side plates positionedin said side bores whereby the side edges of said tread member and thesides of said side plates are in planar alignment.

8. An abrasive wheel of the class described comprising a cylindrical hub'adapted to be mounted on a motor shaft, a pair of circular side platesattached to the sides of said hub, each of said side plates having aperipheral row of spaced elongated slots therein adjacent their outerperipheries, a rubber tread member in the form of a ring positionedbetween said side plates, a peripheral row of pin members thereinextending beyond each of the side walls of said ring member and receivedin the elongated slots of said side plates for controlling the positionof said tread member, said tread member having shallow circular recessesin opposed side walls to receive said side plates, said recesses beingas deep as the thickness of said plates.

References Cited in the le of this patent UNITED STATES PATENTS1,186,058 Woods June 6, 1916 2,236,709 Hillix Apr. l, 1941 2,410,536Vonnegut Nov. 5, 1946 2,795,902 Miller June 18, 1957

